1. Field of the Invention
The present invention relates to a battery cell having a battery case and a frame and, more particularly a battery cell having battery case and a frame, where the frame includes a venting guiding portion.
2. Description of Related Art
A battery module including a plurality of battery cells as unit batteries is preferably manufactured so as to have as small a size and weight as possible. For this reason, a prismatic battery or a pouch-shaped battery, which can be stacked with high integration and has a small weight to capacity ratio, is usually used as a battery cell of the battery module. In particular, much interest is currently focused on the pouch-shaped battery, which uses an aluminum laminate sheet as a sheathing member, because the pouch-shaped battery is lightweight, the manufacturing cost of the pouch-shaped battery is low, and it is possible to easily modify the shape of the pouch-shaped battery.
Gas may be generated in the battery cell as the unit battery when the battery cell operates in an abnormal state due to overcharge, overdischarge, overheating, external impact, etc. For example, gas is generated in an overheated battery and the gas pressurized by a pouch-shaped battery case accelerates decomposition of battery elements. As a result, the battery is continuously overheated and gas is further generated in the overheated battery. When overheating of the battery and generation of gas in the overheated battery reach certain critical points, the battery may catch fire or explode. Furthermore, in a case in which a plurality of unit batteries clusters are provided in a limited space, such as in a battery module, a large scale accident may occur.
Consequently, it is necessary to provide a structure that is capable of preventing combustion or explosion of a battery cell when gas is generated in the battery cell.
In addition, in a case in which a battery module is manufactured using a plurality of battery cells, a plurality of members for mechanical fastening and electrical connection between the battery cells is generally needed and, as a result, a process of assembling the mechanical fastening and electrical connection members is very complicated. Furthermore, there is needed a space for coupling, welding, or soldering the mechanical fastening and electrical connection members with the result that the total size of a system is increased. The increase in size of the system is not preferable in the aspect of spatial limitations of an apparatus or device in which a middle or large-sized battery module is installed. Moreover, the middle or large-sized battery module must be configured to have a more compact structure such that the middle or large-sized battery module can be effectively installed in a limited inner space, such as a vehicle.
In particular, a plurality of parts is needed to stack a plurality of battery cells in a fixed state. For example, it is necessary to stably fix the battery cells in place using battery cell fixing parts. As a result, an assembly process is complicated and difficulty in the manufacturing process is increased. In addition, volume and weight of the battery module are increased and the manufacturing cost of the battery module is raised.
Therefore, there is a necessity for a battery module which can be manufactured to have a simple and compact structure, in which the number of parts constituting the battery module is reduced to improve efficiency of an assembly process while decreasing the manufacturing cost of the battery module, and which is configured to have a structure for preventing combustion or explosion of a battery cell when gas is generated in the battery cell.